A printed circuit board mounted with electronic components is installed within an electronic device. In addition, the printed circuit board may be mounted with, for example, a capacitor in order to cut off a noise in a signal. As for the capacitor, for example, a compact and chip-type capacitor that uses a ceramic dielectric body is available.
Electronic devices have been continuously miniaturized. Accordingly, a capacitor mounted on a printed circuit board is also required to be miniaturized. However, when a component to be mounted on a printed circuit board is miniaturized, the accuracy of a mounter used in an assembly factory shall be improved. Accordingly, in recent years, there has been proposed, for example, a printed circuit board in which a capacitor is embedded.
In a printed circuit board provided with a capacitor in which an outer electrode is formed in a tubular shape on an inner circumferential surface of a hole formed in the board, a material serving as a dielectric body is filled inside the outer electrode, and a rod-shaped inner electrode is formed so as to penetrate the dielectric body, for example, a terminal of an electronic component mounted on the printed circuit board is mounted to an end portion of the inner electrode. However, in the case where an input/output route of a signal leading to the capacitor installed in the printed circuit board extends from the outermost layer of the printed circuit board such as, for example, a land installed in the end portion of the inner electrode, a noise is likely to be added to the signal. Furthermore, in the case where a capacitor is formed in a printed circuit board having a plurality of wiring layers, the capacitor may not be connected to a wiring line of a desired wiring layer when an input/output route of a signal leading to the capacitor is limited to the outermost layer of the printed circuit board.
The following are reference documents.
[Document 1] Japanese Laid-Open Patent Publication No. 2008-028188 and
[Document 2] Japanese Laid-Open Patent Publication No. 2000-188448.